Visual quality of printed surfaces: Study of homogeneity

David Nébouy (1) , Mathieu Hébert (1) , Thierry Fournel (1) , Jean-Luc Lesur (2)

1 LHC - Laboratoire Hubert Curien
2 Gemalto [Meudon]

This paper introduces a homogeneity assessment method for the printed versions of uniform color images. This parameter has been specifically selected as one of the relevant attributes of printing quality. The method relies on image processing algorithms from a scanned image of the printed surface, especially the computation of gray level cooccurrence matrices and of objective homogeneity attribute inspired of Haralick's parameters. The viewing distance is also taken into account when computing the homogeneity index. Resizing and filtering of the scanned image are performed in order to keep the level of details visible by a standard human observer at short and long distances. The combination of the obtained homogeneity scores on both high and low resolution images provides a homogeneity index, which can be computed for any printed version of a uniform digital image. We tested the method on several hardcopies of a same image, and compared the scores to the empirical evaluations carried out by non-expert observers who were asked to sort the samples and to place them on a metric scale. Our experiments show a good matching between the sorting by the observers and the score computed by our algorithm

Mots clés: Print quality assessment; Halftoning; Quality index; Quality attributes; Uniformity; Gray-level co-occurrence matrix; Human Visual System; Appearance; Scanner; Printing technologies

Domaines: Optique / photonique

David Nébouy, Mathieu Hébert, Thierry Fournel, Jean-Luc Lesur. Visual quality of printed surfaces: Study of homogeneity. Proceedings of SPIE, the International Society for Optical Engineering, 2014, pp.9016-12. ⟨hal-00962259⟩